.alpha.'-Halo .alpha.,.alpha.-disubstituted .alpha.-amino ketones are useful as intermediates in the synthesis of .alpha.,.alpha.-disubstituted azetidonones, as set forth in the co-pending applications of William W. Hargrove, Ser. No. 502,331 filed Oct. 22, 1965, now U.S. Pat. No. 3,481,920 issued Dec. 2, 1969 and Ser. No. 790,852, filed Jan. 13, 1969, now U.S. Pat. No. 3,494,964 issued Feb. 10, 1970.
A synthesis of .alpha.'-halo .alpha.,.alpha.-disubstituted .alpha.-amino ketones is described in U. S. Pat. No. 3,481,920. According to this synthesis the desired product is obtained by treating a glacial acetic acid solution of the amino ketone with the appropriate halogen. The product is isolated in the form of the acid addition salt of Formula I. This simple convenient, and easily performed preparation has been found to possess certain limitations, e.g., in those compounds where R.sup.3 represents a monophenyl-substituted lower alkyl group, halogenation appears to occur in the alkyl portion of said group.
It is an object of this invention to provide a method of obtaining .alpha.'-halo .alpha.,.alpha.-disubstituted .alpha.-amino ketones, which method avoids the undesirable aspects of previous methods.